This project explores capture and recapture data for six chickadee species across North America using the MAPS (Monitoring Avian Productivity and Survivorship) dataset. The goal is to visualize spatial distributions, estimate species ranges, and assess trends in abundance and recapture rates over time.
The chickadee species included are as follows:
* Black-Capped Chickadee (BCCH)
* Boreal Chickadee (BOCH)
* Carolina Chickadee (CACH)
* Chestnut-Backed Chickadee (CBCH)
* Mountain Chickadee (MOCH)
* Carolina x Black-Capped Hybrid (CBCC)
capture_data <- read_csv("MAPS_BANDING_capture_data.csv")
location_data <- read_csv("MAPS_STATION_location_and_operations.csv")
joined_data <- left_join(capture_data, location_data, by = c("LOC", "STA", "STATION"))
dat <- joined_data %>%
select(LATITUDE, LONGITUDE, LOC, STA, STATION, DATE, C, BAND, SPEC, AGE, SEX,
F, STATUS) %>%
rename(latitude = LATITUDE, longitude = LONGITUDE, location = LOC, station_num
= STA, station_code = STATION, date = DATE, capture_code = C, band_num
= BAND, species = SPEC, age = AGE, sex = SEX, fat = F, status = STATUS)
dms_to_dd <- function(dms_str) {
sapply(dms_str, function(x) {
parts <- strsplit(x, " ")[[1]]
if (length(parts) != 3) return(NA)
deg <- as.numeric(parts[1])
min <- as.numeric(parts[2])
sec <- as.numeric(parts[3])
sign <- ifelse(deg < 0, -1, 1)
deg <- abs(deg)
sign * (deg + min / 60 + sec / 3600)
})
}
dat$latitude <- dms_to_dd(dat$latitude)
dat$longitude <- dms_to_dd(dat$longitude)
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From the analysis above, we can conclude that the chickadee range distributions are as follows:
Important consideration: This analysis is performed on a data set that captures birds at stationary locations, meaning that bird movement is not monitored outside of these set locations. This also means that observations are clustered at predetermined stations and not representative of Chickadee movement and natural ranges. This can only be used as an estimate.
If I were to continue working on this project, I would create models that explore the different demographic and health variables that contribute to whether a chickadee is recaptured or not.